<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <p>111</p>
    <p>111</p>
    <p>222</p>
    <div>123</div>
    <style>
    p{
        color: red;
    }
    div{
        width: 200px;
        height: 200px;
    }
    div{
        min-width: 100px;
        min-height: 100px;
        max-width: 300px;
        max-height: 300px;
    }
    div{
        width: auto;
        height: auto;
    }
    #a{
        background: silver;
        width: 200px;
        height: 200px;
    }
    #b{
        background: gray;
        width: 80%;
        height: 80%;
    }
    </style>
    <div id="a">
        <div id="b">我是html5</div>
    </div>
    <style>
    /* div{
        padding-top: 10px;
        padding-bottom: 10px;
        padding-left: 10px;
        padding-right: 10px;
    }
    div{
        padding: 10px,10px,10px,10pz;
    } */
    /* div{
        padding: 10px,50px,200px;
    } */
    /* div{
        padding: 10px;
    }
    div{
        margin-top: 10px;
        margin-bottom: 10px;
        margin-left: 10px;
        margin-right: 10px;
    } */
    /* div{
        overflow-x: auto;
    }
    div{
        visibility: hidden;
    }
    table tr:first-child{
        visibility: collapse;
    }; */
    span{
        background: silver;
        width: 200px;
        height: 200px;
        display: inline;
    }
    div{
        background: silver;
        width: 200px;
        height: 200px;
        display: inline;
    }
    div{
        background: silver;
        width: 200px;
        height: 200px;
        display: inline-block;
    }
    /* div{
        display: none;
    } */
    #a{
        background: gray;
        float: left;
    }
    #b{
        background: gray;
        float: left;
    }
    #c{
        background: gray;
        float: left;
    }
    </style>
</body>
</html>